hi alex,
been really good to have someone to compare and bounce idea's off,
i'm part way through mounting the bracket for the brake, mounting mine behind the fork (motor side), the bracket is 'pushing' against the fork when applied, meas it takes less strain and can be a lot thinner.
just for 'jigging' i've used a very simple 'L' bracket for the upper fixing bolt, drilled right though the fork, then nut and bolted bracket to secure it.
i will be making a simple straight strap, with a hole to go on the axle (between wheel and fork), that will then be bolted onto the lower brake fixing.
when happy i'll add photos,i'm lucky as i have a spare chassis and forks with steering rod
regs
Alan